Comparison of the Cerumenolytic Activities of New and Currently Used Agents.

OBJECTIVES: This study compared the cerumen dissolution activities of 7.5% sodium bicarbonate, 5% potassium hydroxide, 10% lactic acid, 3% salicylic acid, 10% glycolic acid, and distilled water. METHODS: An in vitro study was conducted with 36 cerumen samples. The cerumenolytic activities of the 6 agents were assessed by recording the degree of cerumen disintegration using digital photography at 15 minutes, 30 minutes, 1 hour, 2 hours, and 12 hours. The undissolved cerumen that remained after 12 hours was removed from the solutions and weighed after drying. RESULTS: Potassium hydroxide showed the fastest cerumenolytic activity, dissolving a moderate amount of cerumen at 30 minutes, while glycolic acid and salicylic acid caused no visible changes in the cerumen samples. Samples treated with potassium hydroxide and sodium bicarbonate exhibited higher degrees of disintegration compared to samples treated with distilled water (odds ratio and 95% CI: 273.237 [0.203-367 470.4] and 1.129 [0.002-850.341], respectively). The greatest reduction in cerumen weight was associated with the use of sodium bicarbonate; however, this result did not reach statistical significance. CONCLUSIONS: Among the solutions tested, 5% potassium hydroxide showed the fastest dissolution activity, yielding moderate disintegration within only 30 minutes. In terms of residual cerumen weight within 12 hours, all solutions exhibited equivalent effectiveness in the disintegration of cerumen.

Upper Airway Areas, Volumes, and Linear Measurements Determined on Computed Tomography During Different Phases of Respiration Predict the Presence of Severe Obstructive Sleep Apnea.

PURPOSE: The objective of this study was to analyze the potential of using low-dose volumetric computed tomography (CT) during different phases of respiration for identifying patients likely to have severe obstructive sleep apnea (OSA), defined as a respiratory disturbance index (RDI) higher than 30. PATIENTS AND METHODS: A prospective study was undertaken at the Ramathibodi Hospital (Bangkok, Thailand). Patients with diagnosed OSA (N = 82) were recruited and separated into group 1 (RDI, ≤30; n = 36) and group 2 (RDI, >30; n = 46). The 2 groups were scanned by low-dose volumetric CT while they were 1) breathing quietly, 2) at the end of inspiration, and 3) at the end of expiration. Values for CT variables were obtained from linear measurements on lateral scout images during quiet breathing and from the upper airway area and volume measurements were obtained on axial cross-sections during different phases of respiration. All CT variables were compared between study groups. A logistic regression model was constructed to calculate a patient's likelihood of having an RDI higher than 30 and the predictive value of each variable and of the final model. RESULTS: The minimum cross-sectional area (MCA) measured at the end of inspiration (cutoff point, ≤0.33 cm2) was the most predictive variable for the identification of patients likely to have an RDI higher than 30 (adjusted odds ratio [OR] = 5.50; 95% confidence interval [CI], 1.76-17.20; sensitivity, 74%; specificity, 72%,), followed by the MCA measured at the end of expiration (cutoff point, ≤0.21 cm2; adjusted OR = 3.28; 95% CI, 1.05-10.24; sensitivity, 70%; specificity, 68%). CONCLUSION: CT scanning at the ends of inspiration and expiration helped identify patients with an RDI higher than 30 based on measurement of the MCA. Low-dose volumetric CT can be a useful tool to help the clinician rapidly identify patients with severe OSA and decide on the urgency to obtain a full-night polysomnographic study and to start treatment.

Computed Tomography Characterization and Comparison With Polysomnography for Obstructive Sleep Apnea Evaluation.

PURPOSE: We hypothesized that computed tomography (CT) combined with portable polysomnography (PSG) might better visualize anatomic data related to obstructive sleep apnea (OSA). The present study evaluated the CT findings during OSA and assessed their associations with the PSG data and patient characteristics. PATIENTS AND METHODS: We designed a prospective cross-sectional study of patients with OSA. The patients underwent scanning during the awake state and apneic episodes. Associations of the predictor variables (ie, PSG data, respiratory disturbance index [RDI]), patient characteristics (body mass index [BMI], neck circumference [NC], and waist circumference [WC]), and outcome variables (ie, CT findings during apneic episodes) were assessed using logistic regression analysis. The CT findings during apneic episodes were categorized regarding the level of obstruction, single level (retropalatal [RP] or retroglossal [RG]) or multilevel (mixed RP and RG), degree of obstruction (partial or complete), and pattern of collapse (complete concentric collapse [CCC] or other patterns). RESULTS: A total of 58 adult patients with OSA were scanned. The mean ± standard deviation for the RDI, BMI, NC, and WC were 41.6 ± 28.55, 27.80 ± 5.43 kg/m2, 38.3 ± 4.3 cm, and 93.8 ± 13.6 cm, respectively. No variables distinguished between the presence of single- and multilevel airway obstruction in the present study. A high RDI (≥30) was associated with the presence of complete obstruction and CCC (odds ratio 6.33, 95% confidence interval 1.55 to 25.90; and odds ratio 3.77, 95% confidence interval 1.02 to 13.91, respectively) compared with those with a lesser RDI. CONCLUSIONS: An increased RDI appears to be an important variable for predicting the presence of complete obstruction and CCC during OSA. Scanning during apneic episodes, using low-dose volumetric CT combined with portable PSG provided better anatomic and pathologic findings of OSA than did scans performed during the awake state.

Clinicopathologic Findings and Treatment Outcome of Laryngectomized Patients with Laryngeal Cancer and Hypopharyngeal Cancer: An Experience in Thailand

Objective: To evaluate the clinicopathologic findings and treatment outcome in laryngectomized patients with laryngeal cancer and hypopharyngeal cancer. Materials and Methods: The authors retrospectively reviewed the medical records of 212 patients who had been newly diagnosed and treated with laryngectomy between January 2000 and December 2010. The age, gender, clinical manifestations, associated predisposing condition, tumor WHO grade, AJCC tumor stage, maximum tumor size, anatomical involvement, type of surgery, postoperative sequelae, treatment and therapeutic outcome were analyzed. Results: The present study included laryngeal cancer (n = 155) and hypopharyngeal cancer (n = 57). The patients' age ranged from 38 to 84 years, with the mean age of 62.08±9.67 years. The common clinical presentations were hoarseness (73.6%), cervical lymphadenopathy (35.8%), sorethroat (22.2%), and odynophagia (14.6%). The laryngeal cancer commonly involves true vocal cord (86.5%), anterior commissure (65.8%), false vocal cord (56.8%), laryngeal ventricle (53.5%), subglottis (47.1%), and paraglotic space (35.5%), respectively. Fifty-three percent of cases had stage IV cancer. The most common postoperative surgical sequela was hypothyroidism (77.8%). The overall 5-year survivals for laryngeal cancer and hypopharyngeal cancer were 55% and 9%, respectively. The 5-year survival for node-negative cases was 61.8% versus 17% for node-positive cases (p< 0.001). AJCC stage of laryngeal cancer and hypopharyngeal cancer was a significant predictor of 5-year survival (p< 0.001 and p = 0.004, respectively). Conclusions: The advanced AJCC stage, advanced T stage, advanced N stage, extracapsular tumor spread, and tumor invasion of false vocal cord, epiglottis, preepiglottic space, paraglottic space, thyroid cartilage, cricothyroid membrane were found to significantly augment the decrease of 5-year survival in laryngeal cancer. Only advanced AJCC stage was significantly associated with 5-year survival rate in hypopharyngeal cancer.

The validity and reliability of Thai Sinonasal Outcome Test-22.

Chronic rhinosinusitis (CRS) symptoms can significantly reduce quality of life. The Sinonasal Outcome Test-22 (SNOT-22) is frequently used to assess this disease-specific quality of life, although it has not been translated into Thai language. We translated the original SNOT-22 questionnaire to Thai using forward-backward technique, and validated it in CRS patients [n = 229, mean age of 52.6 (SD = 15.9)] recruited at outpatient Otolaryngology clinic, Faculty of Medicine Ramathibodi Hospital, Bangkok, Thailand. A construct validity was assessed using factor analysis, reliability was assessed using intra-class correlation coefficient (ICC) after 3 days of taking the first questionnaire, and internal consistency was assessed using Cronbach's alpha. A total of 201 out of 229 patients completed SNOT-22 questionnaire. Factor analysis with oblique rotation was applied and yielded three domains with eigenvalue of 1 or higher. These domains were named as nasal-related, ear-general-psychological, and sleep-related domains. Estimated ICC ranged from 0.49 to 0.71 with a median of 0.64, and Cronbach's alpha was 0.94. The Thai SNOT-22 questionnaire is reliable and valid with three domains. Thai SNOT-22 may be used in research and clinical practice to assess disease-specific quality of life and aid in management plan at CRS clinic.

Fuzzy zoning for feature matching technique in 3D reconstruction of nasal endoscopic images.

3D reconstruction from nasal endoscopic images greatly supports an otolaryngologist in examining nasal passages, mucosa, polyps, sinuses, and nasopharyx. In general, structure from motion is a popular technique. It consists of four main steps; (1) camera calibration, (2) feature extraction, (3) feature matching, and (4) 3D reconstruction. Scale Invariant Feature Transform (SIFT) algorithm is normally used for both feature extraction and feature matching. However, SIFT algorithm relatively consumes computational time particularly in the feature matching process because each feature in an image of interest is compared with all features in the subsequent image in order to find the best matched pair. A fuzzy zoning approach is developed for confining feature matching area. Matching between two corresponding features from different images can be efficiently performed. With this approach, it can greatly reduce the matching time. The proposed technique is tested with endoscopic images created from phantoms and compared with the original SIFT technique in terms of the matching time and average errors of the reconstructed models. Finally, original SIFT and the proposed fuzzy-based technique are applied to 3D model reconstruction of real nasal cavity based on images taken from a rigid nasal endoscope. The results showed that the fuzzy-based approach was significantly faster than traditional SIFT technique and provided similar quality of the 3D models. It could be used for creating a nasal cavity taken by a rigid nasal endoscope.

CT perfusion in predicting treatment response of nasopharyngeal carcinoma.

BACKGROUND: Direct nasopharyngoscope with biopsy is the gold standard for assessing tumor response of nasopharyngeal carcinoma (NPC). It is invasive with risk of hemorrhage or infection. OBJECTIVE: Explore the usefulness of pre-treatment CTperfusion (CTP) and clarify the parameters in predicting the treatment response. MATERIAL AND METHOD: Twelve patients with histologically proven NPC who underwent pretreatment contrast enhanced CT (CECT) and CTP with parameters (blood flow (BF), blood volume (BV) and permeability), followed by CECT at three months after complete concurrent chemo-radiotherapy or radiotherapy were included in this prospective, cross-sectional study. Pre- and post-treatment primary tumor volumes based on free hand drawn region encompassing the entire primary tumor were measured and compared The response to therapy was also assessed by RECIST guideline version 1.1, based on sum of the diameters of longest diameter for primary tumor and minimal transverse diameter for nodal lesions for all target lesions on the pre- and post-treatment imaging, and classified into "Non-response" group and "Complete response" group. Statistical analysis was performed using Pearson 's correlation coefficients and Mann-Whitney U test. RESULTS: Ten and two patients (83.3%, 16.7%) belonged to "Complete response" and "Non-response "groups respectively. Elevated permeability, BF and BV had a following trend of positive correlation with degree of primary tumor volume reduction without statistical significance. The values ofpermeability, BFE and BV had a trend to be higher in "Complete response" group compared with "Non-response" group (p = 0.053, 0.390 and 0.519 respectively). The permeability had the highest predictive value with an area under the ROC curve of 0.95 and cutoff value of 45 ml/100 g/min (sensitivity, 100%; specificity, 90%). CONCLUSION: Pre-treatment CTP can be useful non-invasive tool in predicting treatment response of NPC. Permeability is the excellent parameter used to differentiate between complete and non-response groups.

Evaluation of real-time polymerase chain reaction for detection of the 16S ribosomal RNA gene of Mycobacterium tuberculosis and the diagnosis of cervical tuberculous lymphadenitis in a country with a high tuberculosis incidence.

BACKGROUND: Tuberculous lymphadenitis (TBL) is the most common form of extrapulmonary tuberculosis. Currently, the standard diagnostic test for TBL is culture, which takes more than several weeks to yield results. We studied a real-time polymerase chain reaction (PCR) for rapid detection of Mycobacterium tuberculosis in cervical lymph node specimens obtained from patients in a country where the tuberculosis incidence is high. METHODS: Patients with cervical lymphadenopathy were prospectively enrolled between April 2009 and March 2010. Clinical specimens obtained through fine-needle aspiration (FNA) and excisional biopsy were tested for M. tuberculosis by the COBAS TaqMan MTB Test, a real-time PCR assay for detecting the 16S ribosomal RNA gene of M. tuberculosis. Mycobacterial culture and histopathological findings from tissue biopsy specimens were used as a reference standard for sensitivity and specificity calculations. RESULTS: Of 73 patients, 41 received a diagnosis of TBL. For biopsy specimens, the sensitivity of real-time PCR was 63.4%, and the specificity was 96.9%. For FNA specimens, the sensitivity was 17.1%, and the specificity was 100%. The sensitivity of real-time PCR of biopsy specimens was comparable to that of tissue culture but significant lower than that of histopathological examination (P < .01). CONCLUSIONS: Real-time PCR did not increase the yield for rapid diagnosis of TBL.

Nasopharyngeal carcinoma segmentation using a region growing technique.

PURPOSE: This paper proposes a new image segmentation technique for identifying nasopharyngeal tumor regions in CT images. The technique is modified from the seeded region growing (SRG) approach that is simple but sensitive to image intensity of the initial seed. METHODS: CT images of patients with nasopharyngeal carcinoma (NPC) were collected from Ramathibodi hospital, Thailand. Tumor regions in the images were separately drawn by three experienced radiologists. The images are used as standard ground truth for performance evaluation. From the ground truth images, common sites of nasopharyngeal tumor regions are different from head to neck. Before the segmentation, each CT image is localized: above supraorbital foramen (Group I), below oropharynx (Group III), or between these parts (Group II). Representatives of the CT images in each part are separately generated based on the Self-Organizing Map (SOM) technique. The representative images contain invariant features of similar NPC images. For a given CT slice, a possible tumor region can be approximately determined from the best matching representative image. Mode intensity within this region is identified and used in the SRG technique. RESULTS: From 6,606 CT images of 31 NPC patients, 578 images contained the tumors. Because NPC images above the supraorbital foremen were insufficient for study (6 images from 1 subject), they were excluded from the analysis. The CT images with inconsistent standard ground truth images, metastasis cases, and bone invasion were also disregarded. Finally, 245 CT images were taken into account. The segmented results showed that the proposed technique was efficient for nasopharyngeal tumor region identification. For two seed generation, average corresponding ratios (CRs) were 0.67 and 0.69 for Group II and Group III, correspondingly. Average PMs were 78.17 and 82.47%, respectively. The results were compared with that of the traditional SRG approach. The segmentation performances of the proposed technique were obviously superior to the other one. This is because possible tumor regions are accurately determined. Mode intensity, which is used in place of the seed pixel intensity, is less sensitive to the initial seed location. Searching nearby tumor pixels is more efficient than the traditional technique. CONCLUSION: A modified SRG technique based on the SOM approach is presented in this paper. Initially, a possible tumor region in a CT image of interest is approximately localized. Mode intensity within this region is determined and used in place of the seed pixel intensity. The tumor region is then searched and subsequently grown. The experimental results showed that the proposed technique is efficient and superior to the traditional SRG approach.

A small absorbable stent for treatment of anterior glottic web.

A new one-stage approach for treatment of selected anterior glottic web has been successful. This case report illustrates its simplicity in microlaryngoscopy with complete lysis of the anterior glottic web by CO(2) laser. Then a small neck horizontal incision is made at the level of anterior commissure to gain exposure to thyroid cartilage. Absorbable suture is passed through the midline of thyroid cartilage below and above the anterior commissure. A knot is tied over thyroid ala. The suture acts as a tiny stent to prevent recurrence of the web.

Audiological outcomes of cochlear implantation in Ramathibodi Hospital.

OBJECTIVE: To evaluate the outcomes of the patients at 1-year post cochlear implantation emphasized on audiological outcomes. MATERIALS AND METHOD: Retrospective study of hearing response follow in three, six, and 12 months of 143 ears undergoing cochlear implantation between 1995 and 2009. Only 77 ears were found to have the completed data for analysis. Deaf patients were categorized into five groups in which they were operated by four different cochlear implant devices. The two parameters used to evaluate the outcomes included the aided response (AR), assessing the hearing threshold of cochlear implant user; and the Categories of Auditory Performance (CAP) which assess their auditory receptive abilities. RESULTS: Demographic data showed male:female ratio was 4:3. Age ranged from 2 to 68 years. Although the aided hearing threshold among five groups of deafness showed improvement without statistical difference, the auditory ability showed significance higher score in post-lingual than pre-lingual deaf patients (p < 0.05). Patients with aural communication prior to surgery also showed higher auditory ability than those without aural communication (p < 0.05). The outcomes of CAP were analyzed among patients operated with different cochlear implant devices. Users with Pulsar CI 100 Opus 2, HiRes 90K Auria, and HiRes 90 K Harmony showed better auditory ability than with Combi 40+ Tempo+. Both mean scores of AR and CAP were higher at six and 12 months than at three months. At 12 months the scores were higher than at six months (p < 0.05). CONCLUSIONS: Cochlear implant surgery resulted in good hearing, however the improvement of speech understanding need more time to practice. Patients using cochlear implant at 12 months showed more improvement of hearing and performance than those using for less than 12 months.

Fourteen-years experience with cochlear implantation in Ramathibodi Hospital.

OBJECTIVE: To review the cochlear implant program in Ramathibodi Hospital and share experience of cochlear implantation emphasized on clinical and surgical outcomes. MATERIAL AND METHOD: Retrospective review of 143 ears (140 patients) operated with cochlear implant between 1995 and 2009. The demographic data including etiology of deafness and findings from temporal bone CTscans were reviewed. The authors' experience with cochlear implant surgery in terms of patient selection, patient advisory clinic, necessary equipment, pre- and postoperative evaluations, surgical techniques and complications were discussed. RESULTS: Most congenital origin was unknown etiology and congenital rubella was the most common known cause. From the CT scans of congenital deafness, vestibular aqueduct dilatation was the most common and found in 29.31% while Mondini malformation was shown to be 16.37%. The authors' surgical technique of using the pocket method and designed bony ridge at cortical mastoid rim had helped stabilizing the implant and electrode fancoil. During the last two years, no complication or revision surgery was detected. CONCLUSION: Cochlear implant surgery in both children and adults can result in good surgical outcome and fewer complications under experienced surgeons and a good team.

Association between multidrug resistance-associated protein 1 and poor prognosis in patients with nasopharyngeal carcinoma treated with radiotherapy and concurrent chemotherapy.

ATP-binding cassette (ABC) multidrug transporters have been associated with chemoresistance, which is a major obstacle in attempts to improve clinical outcome of patients with nasopharyngeal carcinoma (NPC). In this study, we investigated 3 ABC multidrug transporters including MDR1, MRP1, and BCRP for their potential as prognostic indicators in patients with NPC. We examined the protein expression profiles of MDR1, MRP1, and BCRP in NPC tissues from 60 patients with advanced stages who were treated with radiotherapy and concurrent chemotherapy. The clinicopathologic features, patterns of treatment failure, and survival data were compared with the transporter expression. Univariate analyses were performed to determine the prognostic factors that influenced treatment failure and patient survival. We found that MRP1 expression was strongly predictive of both 5-year survival (P = .025) and disease-free survival (P < .001). However, neither MDR1 nor BCRP expression was correlated with the clinicopathologic parameters. Interestingly, the incidence of recurrence and metastasis for patients in the MRP1-positive group was significantly higher than that in the MRP1-negative group (P = .003). With multivariate analysis, MRP1 expression at the time of diagnosis before the treatment was identified as an independent prognostic factor for both 5-year survival (P = .041) and disease-free survival (P = .001). MRP1 expression can therefore be used as a potent molecular risk factor and a guide for chemotherapeutic regimens in patients with advanced stages of NPC.